It's no suprise that you think we have have "interpreted" Mark 10:21 in error. Many Christians do when we mention it because they don't want to follow it as it reads literally. You, like so many other Christians, want to bring out your magic decoder ring in determining what is literal and what is metaphor in the bible. You want for instance, the resurrection of Christ to be literal but you want the instructions to give up all you have and trust in God to be metaphor.
Your mentioning of a computer is an example of how your supposed divinely inspired holy book is just a book written by someone who couldn't conceive of communicating with another human being without scrolls or by talking directly to him. He didn't need think you needed anything but your two feet and trust in the divine to get the message out, all leave everythign of importance to you and be like the lilies and the birds. We see that even family should be left behind (Matthew 10, Mark 10:28-29, etc) Now Christians have computers and rely on glurgy emails and websites, soemthing that this person, or God if you believe in it, never thought of.
I am always amused when Christians can come up with "reasons" that God wants them to have material possessions. That's exactly what the "prosperity" minstries do, and that's what you are doing too. When you point the finger at everyone else who you deem has "too much" interest in "material possessions and science" you are a hypocrite. That science is what makes you comfy and what has shown your religion to be largely wrong in everything so far and likely to continue doing that. I might believe your scenario if you used your computer for nothing else but "God's Work" but I really doubt that you do.